The present invention relates to distributed control systems (DCS), and more particularly to batch control of process equipment using various DCS protocols.
A distributed control system (DCS) refers to a control system, usually of a manufacturing system, process or any kind of dynamic system, in which the controller elements are not central in location but are distributed throughout the system, with each component sub-system being controlled by one or more controllers. The entire system is generally networked for communication and monitoring. The distributed controllers control various subsystems, such as process equipment. Many legacy DCS systems provide a mechanism for batch control of process equipment. When installing DCS systems, it is common for one vendor to install an entire DCS. Accordingly, legacy DCS systems typically communicate using vendor specific protocols. As process equipment ages and controllers age, different pieces of equipment and controllers need to be replaced at different times. This can be difficult as different vendors utilize different DCS protocols. Furthermore, it is typically very expensive to completely upgrade DCS systems. Accordingly, in many cases, manufacturing plants end up with automation assets from various vendors that cannot communicate with each other.
In recent years, S88, a standard for the implementation of batch systems, has been defined. S88 provides a consistent set of standards and terminology for batch control. This standard was developed to address problems such as lack of a universal model for batch control, difficulty in communicating user requirements, integration among batch automation suppliers, and difficulty in batch control configuration. The S88 standard provides a number of benefits to manufacturing companies in the process industries. However, for plants using legacy DCS systems, the benefits of S88 have not been achieved without expensive equipment upgrades accompanied by extensive re-engineering.
Accordingly, it is desirable to achieve the benefits of S88 for legacy DCS systems, whose configuration paradigms and run-time communication protocols are not “S88 aware”, without requiring upgrading or reconfiguration of field equipment.